Hi All, While writing a grammar for programs written in the Racket language, I have stumbled upon a problem. In Racket #| starts a multiline comment and |# ends it. The problem is that multiline comments can be nested: #| a comment #| still a comment |# even more comment |# Here is my non-working attempt: repository: multilinecomment: begin: \#\| end: \|\# name: comment contentName: comment patterns: - include: "#multilinecomment" name: comment - match: ([^\|]|\|(?=[^#]))* name: comment The intent of the match patterns are: "#multilinecomment" A multiline comment can contain another multiline comment. ([^\|]|\|(?=[^#]))* The meaning of the subexpressions: [^\|] any characters not an `|` \|(?=[^#]) an `|` followed by a non-`#` The entire expression thus matches a string not containg |# Is it possible to match nested multiline comments correctly? -- Jens Axel Søgaard